1. Technical Field
The invention relates to a memory management method. Particularly, the invention relates to a memory management method for a rewritable non-volatile memory module, a memory controller and a memory storage device using the same.
2. Related Art
Digital cameras, cell phones, and MP3 players have undergone rapid growth in recent years, so that consumer demands for storage media have also rapidly increased. Since a rewritable non-volatile memory module (for example, a flash memory) has characteristics such as data non-volatility, low power consumption, small volume, non-mechanical structure, etc., it is suitable for being built in the aforementioned various portable multimedia devices.
According to the number of bits stored in each memory cell, NAND flash memories are classified into single level cell (SLC) NAND flash memories, multi level cell (MLC) NAND flash memories and trinary level cell (TLC) NAND flash memories, where each memory cell of the SLC NAND flash memory can store one bit (i.e. “1” and “0”), each memory cell of the MLC NAND flash memory can store two bits, and each memory cell of the TLC NAND flash memory can store three bits.
Taking the TLC NAND flash memory as an example, each physical block includes a plurality of physical page sets, and each of the physical page sets includes a lower physical page, a middle physical page and an upper physical page. Generally, the physical blocks in the flash memory are grouped into a plurality of usage areas, and a replacement area also includes a plurality of the physical blocks. When a physical block in the usage area is damaged, the physical block in the replacement area can be used to replace the damaged physical block. However, when the replacement area has no available physical block, it represents that a usage lifespan of the flash memory is ended. Therefore, how to effectively manage the physical blocks to prolong the lifespan of the flash memory is an important issue to be studied by related practitioners.
Nothing herein should be construed as an admission of knowledge in the prior art of any portion of the present invention. Furthermore, citation or identification of any document in this application is not an admission that such document is available as prior art to the present invention, or that any reference forms a part of the common general knowledge in the art.